Comparisons of full correlation analysis (FCA) and imaging Doppler interferometry (IDI) winds using the Buckland Park MF radar

Abstract

Abstract. We present results from three years of mesospheric and thermospheric wind measurements obtained using full correlation analysis (FCA) and imaging Doppler interferometry (IDI) for the Buckland Park MF radar. The IDI winds show excellent agreement with the FCA winds, both for short (2-min) and longer term (hourly, fortnightly) comparisons. An extension to a commonly used statistical analysis technique is introduced to show that the IDI winds are approximately 10% larger than the FCA winds, which we attribute to an underestimation of the FCA winds rather than an indication that IDI overestimates the wind velocity. Although the distribution of IDI effective scattering positions are shown to be consistent with volume scatter predictions, the velocity comparisons contradict volume scatter predictions that the IDI velocity will be overestimated. However, reanalysis of a 14-day data set suggests the lack of overestimation is due to the radial velocity threshold used in the analysis, and that removal of this threshold produces the volume scatter predicted overestimation of the IDI velocities. The merits of using hourly IDI estimates versus hourly averaged 2-min IDI estimates are presented, suggesting that hourly estimated turbulent velocities are overestimated.

The Buckland Park MF radar: routine observation scheme and velocity comparisons

“…Preliminary FCA results are presented by Holdsworth and Reid (1997) and Holdsworth et al (2001). Further FCA results are presented in the accompanying paper Holdsworth and Reid (2004).…”

“…The FCA results have been used to investigate the TSE using the statistical comparison technique of Hocking et al (2001), and the extension described by Holdsworth and Reid (2004). The daily mean relative magnitudes, correlations, "maximum" measurement errors and acceptance rates are shown in Table 3.…”

“…9 presents sample velocity comparisons. Results from specific analyses are presented in more detail in Holdsworth and Reid (1997), Holdsworth et al (2001), , Vuthaluru et al (2002), Holdsworth and Reid (2004), and in a number of papers currently in preparation. …”

Turbulence associated with mountain waves over Northern Scandinavia – a case study using the ESRAD VHF radar and the WRF mesoscale model

“…velocity fluctuations determined by the full correlation (f.c.a.) technique (Briggs, 1984;Holdsworth et al, 2001;Holdsworth and Reid, 2004). The height resolution of the measurements on this occasion was 300 m, and each profile represents an average over 51 seconds, with measurements repeated each 2 min.…”

Dynamical influence of gravity waves generated by the Vestfjella Mountains in Antarctica: radar observations, fine-scale modelling and kinetic energy budget analysis

“…This gives a two-way beam-width of about 98 (see Kirkwood et al, , 2008Valkonen et al, 2010, for the details). With a radar beam steered only at the vertical, MARA measures the height profile of vertical winds determined from the Doppler shift of the returned signal, as well as of the horizontal winds and rms velocity fluctuations determined by the full correlation technique (Briggs, 1984;Holdsworth and Reid, 2004). Moreover the height profile of radar echo power returned from the troposphere and lower stratosphere is supposed to depend on the distance from which the echo is returned, atmospheric density, static stability, humidity gradients and the fine-scale structure of temperature and density fluctuations within the scattering volume (e.g.…”